package server;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Modifier;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Executors;
import java.util.concurrent.RejectedExecutionHandler;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import server.classloader.MyClassLoader;

/**
 * Minicat的主类
 */
public class Bootstrap {

    /**
     * 定义socket监听的端口号
     */
    private int port = 8080;

    public int getPort() {
        return port;
    }

    public void setPort(int port) {
        this.port = port;
    }


    /**
     * Minicat启动需要初始化展开的一些操作
     */
    public void start() throws Exception {

        // 加载解析相关的配置，web.xml
        loadServlet();

        // 定义一个线程池
        int corePoolSize = 10;
        int maximumPoolSize = 50;
        long keepAliveTime = 100L;
        TimeUnit unit = TimeUnit.SECONDS;
        BlockingQueue<Runnable> workQueue = new ArrayBlockingQueue<>(50);
        ThreadFactory threadFactory = Executors.defaultThreadFactory();
        RejectedExecutionHandler handler = new ThreadPoolExecutor.AbortPolicy();

        ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(
                corePoolSize,
                maximumPoolSize,
                keepAliveTime,
                unit,
                workQueue,
                threadFactory,
                handler
        );





        /*
            完成Minicat 1.0版本
            需求：浏览器请求http://localhost:8080,返回一个固定的字符串到页面"Hello Minicat!"
         */
        ServerSocket serverSocket = new ServerSocket(port);
        System.out.println("=====>>>Minicat start on port：" + port);

        /*while(true) {
            Socket socket = serverSocket.accept();
            // 有了socket，接收到请求，获取输出流
            OutputStream outputStream = socket.getOutputStream();
            String data = "Hello Minicat!";
            String responseText = HttpProtocolUtil.getHttpHeader200(data.getBytes().length) + data;
            outputStream.write(responseText.getBytes());
            socket.close();
        }*/

        /**
         * 完成Minicat 2.0版本
         * 需求：封装Request和Response对象，返回html静态资源文件
         */
        /*while(true) {
            Socket socket = serverSocket.accept();
            InputStream inputStream = socket.getInputStream();

            // 封装Request对象和Response对象
            Request request = new Request(inputStream);
            Response response = new Response(socket.getOutputStream());

            response.outputHtml(request.getUrl());
            socket.close();

        }*/

        /**
         * 完成Minicat 3.0版本
         * 需求：可以请求动态资源（Servlet）
         */
        /*while(true) {
            Socket socket = serverSocket.accept();
            InputStream inputStream = socket.getInputStream();

            // 封装Request对象和Response对象
            Request request = new Request(inputStream);
            Response response = new Response(socket.getOutputStream());

            // 静态资源处理
            if(servletMap.get(request.getUrl()) == null) {
                response.outputHtml(request.getUrl());
            }else{
                // 动态资源servlet请求
                HttpServlet httpServlet = servletMap.get(request.getUrl());
                httpServlet.service(request,response);
            }

            socket.close();

        }
*/

        /*
            多线程改造（不使用线程池）
         */
        /*while(true) {
            Socket socket = serverSocket.accept();
            RequestProcessor requestProcessor = new RequestProcessor(socket,servletMap);
            requestProcessor.start();
        }*/

        System.out.println("=========>>>>>>使用线程池进行多线程改造");
        /*
            多线程改造（使用线程池）
         */
        while (true) {

            Socket socket = serverSocket.accept();
            RequestProcessor requestProcessor = new RequestProcessor(socket, servletMap);
            //requestProcessor.start();
            threadPoolExecutor.execute(requestProcessor);
        }


    }


    private Map<String, HttpServlet> servletMap = new HashMap<String, HttpServlet>();
    private static List<String> list = new ArrayList<>();
    public static Map<String, Class> httservlet = new HashMap<>();
    public static Map<String, Class> child = new HashMap<String, Class>();

    public static Map<String, Object> classS = new HashMap<>();


    /**
     * 加载解析web.xml，初始化Servlet
     */
    private void loadServlet() {
        InputStream resourceAsStream = this.getClass().getClassLoader()
                .getResourceAsStream("web.xml");
        SAXReader saxReader = new SAXReader();

        try {
            Document document = saxReader.read(resourceAsStream);
            Element rootElement = document.getRootElement();

            List<Element> selectNodes = rootElement.selectNodes("//servlet");
            for (int i = 0; i < selectNodes.size(); i++) {
                Element element = selectNodes.get(i);
                // <servlet-name>lagou</servlet-name>
                Element servletnameElement = (Element) element.selectSingleNode("servlet-name");
                String servletName = servletnameElement.getStringValue();
                // <servlet-class>server.LagouServlet</servlet-class>
                Element servletclassElement = (Element) element.selectSingleNode("servlet-class");
                String servletClass = servletclassElement.getStringValue();

                // 根据servlet-name的值找到url-pattern
                Element servletMapping = (Element) rootElement.selectSingleNode(
                        "/web-app/servlet-mapping[servlet-name='" + servletName + "']");
                // /lagou
                String urlPattern = servletMapping.selectSingleNode("url-pattern").getStringValue();
                servletMap.put(urlPattern, (HttpServlet) Class.forName(servletClass).newInstance());

            }
            String path = "";
            String osName = System.getProperty("os.name");
            System.out.println(osName);
            if (osName.startsWith("Mac OS")) {
                // 苹果
                path = "/Users/webapps";
            } else if (osName.startsWith("Windows")) {
                // windows
                path = "D:\\webapps";
            } else {
                // unix or linux
            }
            this.getWebapps(path, path);


        } catch (DocumentException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }

    }


    /**
     * Minicat 的程序启动入口
     */
    public static void main(String[] args) throws Exception {
        Bootstrap bootstrap = new Bootstrap();
        try {
            // 启动Minicat
            bootstrap.start();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }


    private void getWebapps(String classPaths, String path) {
        try {
            MyClassLoader myClassLoader = new MyClassLoader(classPaths);
            //包名+类名
            File file = new File(classPaths);
            doPath(file, path);
            for (String classPath : list) {
                Class<?> c = myClassLoader.loadClass(classPath);
                Class<?> superclass = c.getSuperclass();
                Package aPackage = c.getPackage();
                String name = "";
                if (null == aPackage) {
                    String[] n = c.getName().split("\\.");
                    name = n[0];
                } else {
                    name = aPackage.getName();
                }

                if (null != superclass) {
                    System.out.println(superclass.getSimpleName());
                    if (superclass.getSimpleName().contains("HttpServlet")) {

                        System.out.println(name);
                        child.put(name, c);
                        LagouServlet httpServlet = new LagouServlet();
                        servletMap.put("/" + name, httpServlet);


                    }
                }
                boolean anAbstract = Modifier.isAbstract(c.getModifiers());
                System.out.println(anAbstract);
                if (!Modifier.isAbstract(c.getModifiers()) && !c.isInterface()) {
                    classS.put("/" + name + "" + c.getSimpleName(), c.newInstance());
                    String simpleName = c.getSuperclass().getSimpleName();
                    classS.put("/" + name + "" + simpleName, c.newInstance());
                    if (c.getSimpleName().contains("Request")) {
                        classS.put("/" + name + "" + "Request", c.newInstance());
                    }
                    if (c.getSimpleName().contains("Response")) {
                        classS.put("/" + name + "" + "Response", c.newInstance());
                    }
                }

                if (c.getSimpleName().contains("HttpServlet")) {
                    httservlet.put("/" + name, c);
                }

            }
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    private void doPath(File file, String path) throws Exception {
        // 文件夹，遍历
        if (file.isDirectory()) {
            File[] files = file.listFiles();
            for (File f1 : files) {
                doPath(f1, path);
            }
        } else {
            // 文件，直接添加
            if (file.getName().endsWith(".class")) {
                String className = file.getPath();
                className = className.replace(path + "\\", "");
                className = className.replace("\\", ".")
                        .replace("/", ".")
                        .replace(".class", "");
                System.out.println(className);
                list.add(className);
            }
        }
    }
}
